Keywords
finger injuries - amputation - hand injuries - wound healing
Introduction
Fingertip injuries are among the most common injuries of the hand, resulting in ∼
4.8 million annual visits to emergency services.[1] The wide variety of surgical techniques described can be confusing, and the clinical
evolution and final results are affected by the chosen method. The needs of the patient
necessity and the experience of the specialist must be taken into consideration to
make a decision.[2] Some objective considerations in order to choose the appropiate technique are: the
angle of tissue loss, bone exposure, the condition of the amputated portion, injuries
to the adjacent fingers, the affected finger, and the extension of the defect. Although
there is no strict treatment algorithm, the objectives should be minimization of pain,
optimization of the healing time, preservation of sensitivity and function, limitation
of deformities in the nail plate, reduction of the time until return to work and,
if possible, fostering of cosmetic results, highlighting the preservation of the greatest
possible length. Although there are different surgical techniques for the reconstruction
of the defects, the conservative treatment by secondary wound healing yields favorable
results.[3]
[4]
[5]
[6]
[7]
In our center there was no experience related to the conservative treatment. Fingertip
amputations were previously treated with conventional surgical techniques (VY flaps
or free skin graft), until conservative techniques became the standard for these injuries
as part of the initial management and, most of the time, as the definitive treatment.
The objective of the present study is to analyze the evolution, the final results,
and the incidence of complications among patients treated by secondary healing and
to compare the results obtained through four different types of injuries according
to the Allen classification.
Methods
The present study was approved by the research and ethics committees of the institution.
This is an observational, retrospective, comparative, analytical study performed in
patients with traumatic fingertip amputations between April 2017 and May 2019. The
amputated tips were reviewed and categorized into four types according to the Allen
classification. The initial management was performed in the emergency room, following
aseptic techniques and under local anesthesia. All patients included were followed
up for a minimum period of six months. Patients injured by animal or human bites,
and those with initial management in another institution or with incomplete follow-up,
were excluded. The extent of the injuries was determined according to Allen's classification.[8] General characteristics of the study population and the duration of the treatment
are described. Early and late complications in each treatment group are also described,
and the need for revision treatment and preservation of the initial length were evaluated.
The relation between these variables and the mechanism and extent of injury were analyzed.
Statistical Analysis
The resulting information was analyzed in the Statistical Package for the Social Sciences
(IBM SPSS Statistics for Windows, IBM Corp., Armonk, NY, United States) software,
version 25.0. For the statistical analysis, the Chi-squared test and the Kruskal-Wallis
test were used. The level of significance was established as p ≤ 0.05.
Secondary Healing Protocol
In the emergency room, the affected finger is put under regional anesthesia with the
conventional technique, with 2% simple lidocaine. The wound is irrigated with sterile
saline solution and gently debrided with sterile gauze. Amputations with exposure
of the distal phalanx were remodeled with gouge and rasp at the level of the edge
of the pulp. Ketanserin gel (Sufrexal, Janssen-Cilag, Beerse, Belgium) was applied
throughout the extent of the amputation; then, a semipermeable adhesive membrane (Tegaderm,
3M, Saint Paul, MN, United States) was applied to cover the defect. Finally, the entire
finger circumference from the distal interphalangeal to the metacarpophalangeal joints
was covered with sterile gauze and fixed with surgical tape (Micropore, 3M), and a
tubular elastic net was fixed to the base of the affected finger. Every patient received
prophylactic oral antibiotic and tetanus toxoid reinforcement vaccination. The patients
were evaluated after 3 to 5 days in an outpatient clinic, where they underwent wound
cleaning by irrigation with sterile saline solution without debridement; then, ketanserin
gel was reaplied, and the wound was covered again with a new semipermeable adhesive
membrane, a procedure repeated weekly until epithelialization of the defect was achieved.
Results
Between April 2017 and May 2019, 127 fingertip injuries were treated in the emergency
room by the trauma service ([Table 1]). The average age of the patients was of 28.33 years (range: 1 to 76 years), with
a predominance of male subjects (82.7%; n=105). The most commonly affected finger
was the middle finger (31.5%; n = 40), and the most common mechanism of injury was crushing (70.9%; n = 90). Most injuries were classified as Allen type 2 (42.5%; n = 54) ([Fig. 1]). The overall average duration of treatment was 4.3 weeks, and was found to be directly
proportional to injury severity according to Allen's Classification (p <0.001). From the total amount of fingertips treated, 18.9% (n=24) presented a complication,
the 3 most frequent being hyperalgesia (10.2%; n = 13), persistent phalanx exposure (5.5%; n = 7), and seroma (2.4%; n = 3). Wound infection was only present in one patient, and it was resolved with the
use of short-course oral antibiotics ([Fig. 2]). These complications had a higher incidence in patients classified as Allen type
2 (45.8%; n=11), followed by type 1 (25%; n=6), 4 (16.6%; n=4) and 3 (12.5%; n=3).
The amount of patients classified as Allen type 2 might explain the higher incidence
of complications found when compared with those classified as Allen type 3. The Allen
classification was significantly related to the development of complications (p ≤ 0.05) ([Table 2]).
Table 1
|
Mean age (years)
|
28.33
|
|
Gender: % (
n
)
|
|
|
Male
|
82.7 (105)
|
|
Female
|
17.3 (22)
|
|
Diabetes mellitus: % (
n
)
|
0.8 (1)
|
|
Smoking: % (
n
)
|
12.6 (12)
|
|
Mechanism of injury: % (
n
)
|
|
|
Crushing
|
70.9 (90)
|
|
Cutting
|
29.1 (37)
|
|
Allen classification: % (
n
)
|
|
|
Type 1
|
32.3 (41)
|
|
Type 2
|
42.5 (54)
|
|
Type 3
|
17.3 (22)
|
|
Type 4
|
7.9 (10)
|
|
Complications: % (
n
)
|
|
|
Wound infection
|
0.8 (1)
|
|
Seroma
|
2.4 (3)
|
|
Persistent bone exposure
|
5.5 (7)
|
|
Painfull fingertip
|
10.2 (13)
|
|
Fingertip necrosis
|
–
|
|
Pain related to nail deformity
|
–
|
|
Revision treatment: % (
n
)
|
6.3 (8)
|
|
Lenght shortening after failure: % (
n
)
|
1.6 (2)
|
|
Average healing time (weeks)
|
4.31
|
Fig. 1 A 68-year-old male patient with an Allen type 2 injury compromising the third and
fourth fingers. (A) Acute presentation. (B) After five weeks under the secondary healing protocol.
Fig. 2 A 49-year-old female patient with an Allen type 3 injury on the thumb. (A-C) Acute presentation. (D-F) After six weeks under the secondary healing protocol. An asymptomatic nail deformity
is shown.
Table 2
|
Complications (n)
|
p-value
|
|
Yes
|
No
|
|
Diabetes mellitus (n = 1)
|
1
|
0
|
< 0.05
|
|
Smoking (n = 16)
|
2
|
14
|
> 0.05
|
|
Mechanism of injury (n = 127)
|
|
Cutting (n = 37)
|
6
|
31
|
> 0.05
|
|
Crushing (n = 90)
|
18
|
72
|
|
Allen Classification (n = 127)
|
|
Type 1 (n = 41)
|
6
|
35
|
< 0.05
|
|
Type 2 (n = 54)
|
11
|
43
|
|
Type 3 (n = 22)
|
3
|
19
|
|
Type 4 (n = 10)
|
4
|
6
|
Finally, we also found a statistically significant (p ≤ 0.0001) relationship between the Allen classification and the preservation of the
maximum length of the fingertip; the need to shorten the initial length to achieve
closure was reported in 2 patients (1.6%) classified as Allen type 2.
Discussion
Fingertips amputations are among the most commonly treated work accidents worldwide,
although there is no consensus regarding their treatment. In developed countries,
the management is reported to be increasingly in favor of microsurgery techniques;
however, in the United States, only 15% of hospitals perform reimplantation surgeries.
Less than 10 surgeries per year are reported, that is, only 14% of fingertip injuries
are treated with this method, while, in Japan, 29% of the cases are treated microsurgically.[9] Another alternative is amputation or remodeling. In the cases revised in the present
study, remodeling as a primary treatment, that is, surgical shortening to achieve
secondary healing, was only offered to 22.7% (n=45) of the patients. The remaining
77.3% (n=155) were submitted to some form of reconstructive treatment, either conservative
or surgical, therefore enebaling the preservation of as much length as possible, and,
consequently, obtaining both a better functional and cosmetic result in those patients
with no clinical restrictions. This surgical shortening is still the initial treatment
in many centers, since it enables a prompt return to work. Its indications and technique
show the heterogeneity observed in the management of hand injuries. In a study[10] conducted among 592 members of the American Society for Surgery of the Hand, 56%
showed a preference for disarticulation over trans-bone amputation, and only 7% preferred
to adjust the level of amputation according to the closure, in an attempt to preserve
as much as possible the length of the finger. The demographics of the subjects of
the present study is similar to to those reported in other series[7]
[11]
[12] with a predominance of young men with crushing injuries, and the second and third
fingers being the most commonly affected, as reported by Torres- Fuentes et al.[12] The diversity of studies with different treatment proposals for the management of
these injuries demonstrates the variability in opinion of hand surgeons, plastic surgeons,
and orthopedic surgeons. Likewise, the diversity of classifications described in recent
years only complicates the unification of criteria.[13]
[14] According to the Allen classification, most of the injuries were type 2, a group
in which the treatment with advancement flaps has traditionally been considered suitable,
particularly Atasoy VY flaps; however, skin borders are frequently irregular or very
damaged, and resection must be done before advancing the flap. Type-1 Allen lesions
are traditionally considered as irrefutable candidates for the conservative management
with secondary healing, but not types 3 and 4. In the present study, 25.3% of fingertip
amputations treated by secondary healing were classified as types 3 and 4. If we consider
the total of amputations treated conservatively, only 6.3% (n=5) required additional
interventions due to complications. Therefore we can assert that injuries of greater
extension than Allen's 1 and 2, may be safely managed with this modality of treatment.
The noteworthy benefits observed include: simplicity, low cost, reproducibility, availability
of material resources, adequate attachment; it can be used safely in diabetic patients
and in those with a history of smoking.In the case of pediatric or apprehensive patients,
it does not require painful procedures or procedures performed in the operating room,
avoiding the risks of anesthesia. On the other hand, the main disadvantage is the
long duration of treatment, which results in a relatively long period of inability
to return to work, this is similar to the periods reported by van den Berg et al.[7] Some patients were initially anxious about the smell and exudate produced within
the first weeks; however, after an explanation, they were satisfied. Psychological
factors have already been related to negative impacts on the functional perception
after the treatment, greater pain intensity, and an increase in the period until the
return to work. Therefore, the identification and treatment of symptoms of depression
will contribute to facilitate the recovery.[15]
The protocol used for secondary healing has demonstrated effectiveness and safety
in the population studied, and allowed us to demonstrate the capacity of tissue regeneration
at least in this portion of the human body, a controversial and current issue.[16]
It is important to declare that the decision to use ketanserin gel is based on its
wide commercial availability in our country and on the experience obtained in the
treatment of vascular and diabetic ulcers; however, a recent Cochrane meta-analysis[17] showed inconclusive results regarding its effectiveness compared to that of other
substances. Since other topical agents, such as petroleum jelly and silver sulphadiazine,
have also been described for the conservative management of fingertip amputations,[6] we believe the results shown in the present study cannot be directly related to
ketanserin, but to a microenvironment rich with the proper growth factor, humidity
control, and hygiene obtained through a close follow-up and early interventions, as
needed.
To demonstrate the superiority of this method over the surgical approach, studies
with a randomized, prospective design are necessary to objectively assess the results
at the end of each treatment. Meanwhile, and given the limitation in material and
human resources for the application of microsurgery techniques worldwide, any treatment
option that demonstrates acceptable cosmetic results, a prompt reintegration into
work activity, and good functional results should be considered an alternative by
the surgeon.
Conclusion
Secondary healing with the described protocol has demonstrated to be effective and
safe in the management of Allen types 1 and 2 fingertip amputations, and satisfactory
results were obtained in some cases of Allen type lesions; therefore, it should be
considered as a therapeutic option even in lesions with great extentions.
